The real world impact of vertical integration on prices for consumers remains a controversial topic. Economic theory suggests that there are multiple effects of vertical integration on prices which work in opposite directions. This paper employs high frequency panel data from a regional U.S. market to determine which effects are dominant at retail gasoline stations. Using two different techniques, I find that vertically-integrated company-operated gasoline stations charge prices five to eleven cents lower than non-integrated, lessee-operated gasoline stations.